Chables jackson



UNITED STATES PATENT OFFICE.

CHARLES JACKSON, OF 134- ROBIN HOOD CHASE, COUNTY OF NOTTINGHAM, ENGLAND.

MANUFACTURE OF HARDENED ASBESTUS.

SPECIFICATION forming part. of Letters Patent No. 359,156, dated March 8, 1887.

Application tiled October 4, 1886. Serial No. 2 5,102. No specimens.) Patented inEngland October S, 1885, No. 11,976, and in France July 21, I886, No.177,51i1.

To aZZ whom it may concern.-

Be it known that 1, CHARLES JACKSON, a subject of the Queen of Great Britain, engineer, residing at 134c Robin Hood Chase, county of 5 Nottingham, England, have invented certain new and useful Improvements in the Manufacture of Hardened Asbestos, of which the following is a specification.

This invention has for its object improvements in the manufacture of hardened asbestus, (for which I have received Letters Patent in Great Britain, No. 11,976, dated October 8, 1885, and in France N o. 17 7, 531, dated July 21, 1886.)

I mix asbestos in a fibrous condition with a liquid binding materialsuch as shellac dissolved in spirit. I make up the material into the form required, and thoroughly consolidate it by heavy pressure. At the same time that 20 the material is under preSSureI expose it to heat to perish the binding material and render it insoluble. Usually, after the material has been exposed to pressure to mold it into form and has been heated to partly perish the adhesive material, I expose it to a heavy pressure in heated dies, and afterward I again heat the molded article in an oven, )refcrably at a higher temperature than previously, to complete the perishing; also, according to my invention, Icombine metal with asbestos and a binding material and harden the preparation by pressure and heat. Thereby I impart to the hardened asbestus greater strength and durability and obtain other advantages.

55 In order that my invention maybe fully understood and readily carried into effect, I will proceed to describe more fully the manner in which I prefer to operate.

I sometimes commence by forming the ashese tus fiber into a coarse thread. At other times I use the asbestus fiber without this previous preparation.

Where it is necessary to resist wear by friction the fiber should be spun, and as far as possible the fiber should be exposed endwise in the finished article. In other cases this A thick solution of ward cut from the fabricand superposed,the one on the other,to build up the form required, and they are consolidated by pressure in a mold. When the form required isintricate it is often more convenient to wind the loose fiber about a mandrel, to obtain asuitable mass, and then to further shape it by pressure in dies. In the process of building up the form, I repeatedly saturate the asbestus with the binding material, and after each treatment I submit the mass to long drying in the ventilated dryingroom. The harder and closer the product required the more of the binding material should be incorporated with the asbestus in these earlier stages. \Vhen thus built up and dried the article is reduced approximately to the form required by pressure in metal molds. At this stage a moderate pressure only is required. The molded article then goes back to the ventilated d rying-room, where it should remain for some weeks. It is then again pressed, and this time it should be exposed to a very heavy pressure,amountin g to many tons on the square inch, and the heavier the better. The molded article is then passed into an oven heated to about 2 50 Fahrenheit, where it-remains for eight or ten hours, until it appears hard anddry. After the article comes from the oven it is again exposed to pressure, and in this case heat is also necessary, as the material would not be condensed sufficiently by a cold pressure. The molds employed (of which the shape,of course, depends on that of the article to be produced) are heated to 350 or 400, and in these molds the article is exposed to the same heavy pressure as beforethe higher the better. If the molded article requires to be fitted into a piece of metal for example, if it be a valve-facing and is to be set into a groove in the metal valveit is atthis stage that the molded asbestus is set into its place. The mold is made to receive the meta-l valve (which is also heated) and the pressure drives the asbestus home into its recess. After the hot-pressure the article is again passed into an even, where a tempera. ture of 300 to 400 is maintained, say, for ten hours. After leaving the oven the article is, if necessary, smoothed and polished; ready for use. When the article is to be exposed to high temperatures in use the temperatures employed in the manufacture should be such as to exceed by at least 50 the temperature to which the article will be afterwards exposed. In high temperatures stoving varnish is more suitable than shellac solution.

Hardened asbestus produced in this way is applicable to a great number of uses. Thus it,

, ings, and many other articles.

I sometimes combine metal with the asbestus and binding material. Thus I form a stout and durable board or panel with a surface of hardened asbestus by taking a sheet of iron and perforating it, by preference, with small holes, leaving the edges of the holes preferably rough and jagged. I then lay on the metal sheet sheets of thin asbestus felt saturated with binding material and dried. I consolidate the whole by a moderate pressure, then dry the compound sheet further and expose it to a heavy pressure. Next I stove it. Then I expose it to pressure between heated surfaces, and finally again stove it, all in a similar manner to that previously described;

also, I combine metal in some cases in the form of wire with the prepared asbestus. I use soft-steel wire, usually in the form of spirals. The spirals are embedded in the prepared abestus, when this is put together into the shape required. The wire, together with the prepared asbestus, goes through all the processes, as already described, and becomes embedded in the article, to which it gives strength and toughness. I also combine metal with asbestus by drawing down small'tubes of 1 steel or other metal onto cords of prepared asbestus. I cover such tubes externally with prepared asbestus and then accumulate them side by side into a block. I expose the block to heat in an oven, and thus form the whole into a mass. This method is applicable where a very durable material under friction is required. ends of the tubes.

Another way in which I combine asbestus with metal is to take threads of the prepared asbestus and coat them with metal by electrodepositiona process well understood. Thus I coat asbestus threads with gold, and I use such threads to make gold lace. Such gold lace, when it becomes tarnished or discolored, can be cleaned with acid.

certained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. The improvement in the manufacture of articles of hardened asbestus, consisting in combining fibrous asbestus with a binding material rendered liquid in a solvent, drying the material or evaporating off the solvent, pressing the material in molds, exposing the mate rial to heat to perish the binding material, or change it so that it is no longer soluble in the solvent, and pressing the materials in heated molds, substantially as and for the purpose set forth.

2. The manufactureof articles of hardened asbestus by molding or forming a mixture of fibrous asbestus with a liquid binding material to the shape desired, then partially perishing the binding material by heat, then exposing the article simultaneously to heat and heavy pressure, and afterward again exposing the article to heat, substantially as described.

3. The combination of asbestus and a bind ing material, consolidated by pressure and changed or perished by heat, with metal, whereby strength and durability are obtained, substantially as described.

London, September 6, 1886.

CHARLES JACKSON.

Vitnesses:

HERBERT E. DALE, J NO. DEAN, Both of N0. 17 Graccchm'ch. Street, London.

Having now particularly described and as-' The asbestus is exposed only at the 

